1. Technical Field
The present invention relates to the composition and process of preparing granola. In particular, the invention relates to preparing a chewy or crunchy granola such that it can be extruded and thereby formed into a shape of arbitrary size such as a bite-sized piece. In addition, extruded granola may comprise a filling. The process differs from the traditional method of preparation by adding water to a traditional granola mixture, allowing the wet granola dough to soften by the absorption of this added, or extra water, extruding the wet granola dough, cutting the wet granola dough, and finally removing the additional water from the wet granola dough resulting in a finished granola product.
2. Description of Related Art
Granola is a well-known product in the food industry. Granola typically comprises of cereal grains, crisp rice, binder syrup and optionally inclusions, a term in the art for pieces of fruit, nuts, or chocolate. Binder syrup is made of an aqueous solution of simple sugars such as corn syrup, glucose, or fructose.
U.S. Pat. No. 4,451,488, issued to Cook, on May 29, 1984, teaches the manufacture of chewy granola. Chewy granola is produced from the ordinary ingredients of granola with the addition of polyhydric alcohols to the binder syrup. Gylcerin and sorbitol are typical polyhydric alcohols added to the binder syrup. Table 1 lists the ingredients in a typical formulation for binder syrup used to produce chewy granola. This formulation for binding syrup includes corn syrup, granulated sugar, corn syrup solids, gylcerin, sorbitol, salt, vegetable shortening, and water, as shown by percent weight in the example listed in Table 1. The granulated sugar is constituted of one or more edible saccharides such as glucose, fructose, maltose, saccharose, honey, or molasses.
TABLE 1Ingredients for Binder Syrup for Chewy GranolaIngredientFormula wt. %Corn Syrup47.0Sugar, granulated15.0Corn Syrup Solids14.0Gylcerin, usp 99%11.0Sorbitol solution, 70% (w/w)3.0Salt1.0Vegetable Shortening8.0Water1.0Total =100.0
Binder syrup is typically prepared by heating the gylcerin, sorbitol, shortening and corn syrup together in a tank to 120° F. The remainder of the ingredients (granulated sugar, corn syrup solids, and salt) are then added to the tank. This mixture is heated to 130° F.; once it has reached this temperature, it is ready to be mixed with the other ingredients of chewy granola shown in Table 2.
A typical chewy granola comprises granola cereal, crisp rice, binder syrup (such as that described above), and inclusions. An example of a specific formulation is shown in Table 2. In this application, all percentages are by weight unless otherwise specified.
TABLE 2Ingredients for a Typical Chewy GranolaFormula wt. %Ingredient(With Inclusions)Granola Cereal47.0Crisp Rice8.0Binder Syrup (see Table 1)34.0Inclusions11.0Total =100.0
The process to create granola bars is relatively straightforward and is shown in FIG. 1. The ingredients 1 are serially added to a continuous mixer 2. The cereal grains and rice are added first, the binder syrup is added second and the inclusions are added last. The inclusions are added last because they may be susceptible to melting from the relatively hot binder syrup. Also, the inclusions are more susceptible to mechanical breakdown and should receive as little processing time as possible.
The mixture at this stage is between ambient temperature (typically 70° F.), and the temperature of the binder syrup (about 130° F.). The overall mixture of granola ingredients, or chewy granola, at this stage is about 6% water by weight. Manufacturers typically use a continuous flow interrupted flight or paddle mixer for production because it mixes the ingredients in the shortest amount of time, transfers the least amount of energy to the ingredients, and causes relatively little mechanical breakdown.
The granola mixture at this point is transferred onto a slabbing conveyor 3 where the mixture is compressed with large rollers 4 to a desired thickness, typically one-half inch. A typical slabbing conveyor is about three feet in width. The mixture is partially cooled 5 as it is rolled out. The slab is sliced 6 and then cut into rectangular bars with a guillotine cutter 7. Each granola bar at this point is about three and one-half inches in length, one to one and one-half inches wide, and weighs between 28 and 35 grams. The bars are cooled 8 to ambient temperature, about 70° F., and packaged 9. The final overall water content is about 6%, about the same as when the granola mixture entered the production process. The composition of the granola does not change throughout the production process.
A traditional apparatus for slabbing, compressing, and cutting granola is illustrated in FIG. 2a and FIG. 2b. FIG. 2a and FIG. 2b are both schematic representations of the process where FIG. 2a is a head-on view and FIG. 2b is a side view. With reference to FIG. 2a, the granola mixture is transferred along a conveyor table 20 from left to right on a conveyor belt 21 (shown in FIG. 2a, but hidden from view in FIG. 2b). The mixture passes beneath a series of product rollers 23 in a void space 22 where the mixture is gradually compressed to a desired thickness, typically one-half inch, creating a continuous sheet of product. After compression, the granola mixture is cooled and passes through a slab slicer 24 in order to divide the continuous sheet into multiple lanes of product. These lanes are then cut into bars by a guillotine cutter 25 before being cooled to roughly ambient temperature and sent to packaging.
The traditional production process is limited in several ways. One limitation is the slicing and cutting speed. The typical production rate is about 6,000 pounds per hour. The conveyor table 20 and guillotine cutter 25 limit the form of granola bars to a rectangle. The guillotine cutter 25 is economically bound to operate within a specific range of operation. It is undesirable for the guillotine cutter 25 to cut granola into smaller bars or pieces because for each cut, granola generates non-recyclable waste fragments. The ratio of waste to finished product increases as the size of the finished granola product decreases. Thus, the smaller the pieces, the higher the waste and hence expense of the product. Another economic limitation is related to production speed. A bite-sized piece of granola is difficult to produce because either the cutting speed may have to be increased beyond its normal limit, or the line speed may have to be slowed with a concomitant reduction in production efficiency. For example, a Quaker Chewy® granola bar is typically about 1.125 inches wide and 3.62 inches long and weighs 29 grams. A line speed of 18 feet per minute requires the guillotine cutter 25 to operate at approximately 60 cuts per minute and yields approximately 6,400 pounds of product per hour. A bite sized piece that is about 1.125 inches wide and 1.125 inches long would require a guillotine cutter 25 to run at 192 cuts per minute to maintain the same line speed and accompanying production rates. Unfortunately, guillotine cutters cannot presently operate faster than 180 cuts per minute. Thus, even when the guillotine cutter operates at the maximum possible speed of 180 cuts per minute, line speed drops to 16.9 feet per minute. Thus, when smaller pieces are produced, overall production is slowed, which results in a higher costs of operation.
There are other known substitutes for cutting granola into bars, but they operate at even slower speeds than the guillotine cutter 25. For example, a Bepex brand ultrasonic guillotine is limited to 80 cuts per minute. A water knife cutter, which makes cuts as it travels back and forth across the belt width, can travel only 100 feet per minute. Thus, for belt width of approximately 3 feet, there is a maximum of only 33 cuts per minute.
Another limitation arises in the traditional production process because Granola is not susceptible to significant manipulation during production because its texture is easily destroyed. The dry grains of granola are susceptible to mechanical destruction and are generally not suited to extrusion or other similar processing. In addition, the traditional apparatus for slabbing, compressing, and cutting granola, as depicted in FIGS. 2a and 2b, does not enable the use of a filling.
Accordingly, a need exists for an improved apparatus and method to create small bite-sized pieces of granola. Further, a need exists for a method to create small granola pieces where the granola maintains its traditional and expected texture, appearance and flavor. Further, a need exists for an apparatus and method to create a granola piece that can be formed into an arbitrary shape or form. Further, a need exists for an improved apparatus and method to produce a granola bite or bar with a filling. Finally, a need exists for an improved apparatus and method to economically create bite-sized pieces and/or filled bars of granola in large quantities.